0.5mm Via Current Calculator
Single Via | Power Via | IPC-2221 trace formula (approximation)
For 0.5mm (20 mil) via with 25µm plating and 1 via(s):
(2.69A per via)
Via Parameters
MOD: VIA_CUR_V1Capacity Check
1 vias × 2.69 A each
Design Recommendations
Via Sizing Tips
- •Standard via (0.5mm) carries 2.69A per via
- •Cross-sectional area: 41,233 µm²
- •For higher current: use larger vias or increase plating thickness
Via Array Guidelines
- •Parallel vias share current equally when properly connected
- •Place vias in grid pattern near power pins for best distribution
- •Consider thermal vias for heat dissipation from power components
Understanding 0.5mm Via Current Capacity
A 0.5mm (20 mil) plated through hole (PTH) via with standard 25µm copper plating is estimated to carry about 2.69A per via with the IPC-2221 trace-current formula applied to the barrel copper. When using 1 parallel via(s), the total current capacity increases to 2.69A, making this configuration suitable for moderate power delivery.
Key Parameters for 0.5mm Via
- Hole Diameter: 0.5mm (20 mil) - power via category
- Plating Thickness: 25µm (standard electroplated copper)
- Board Thickness: 1.6mm (via barrel length)
- Temperature Rise: 10°C (the default used on this page)
- Cross-Section Area: 41,233 µm² per via
- Resistance: 0.682 mΩ per via
Why Use 1 Parallel Via(s)?
A single 0.5mm via provides 2.69A capacity, suitable for signal routing or low-power connections. Single vias minimize PCB real estate usage but limit current capacity. For applications requiring more than 2.69A, consider using multiple parallel vias.
How the Via Current Is Estimated
This page reuses the IPC-2221 trace-current formula I = 0.048 × ΔT^0.44 × A^0.725 (I in A, ΔT in °C, A in mil²), with A taken as the copper ring of the plated barrel. It is an approximation: the formula was fitted to planar traces, not via barrels, so treat the result as a screening estimate and confirm critical designs with your fabricator's plating data and a thermal check. For a 0.5mm hole with 25µm plating the copper ring is 41,233 µm², which gives 2.69A per via at a 10°C rise.
Typical Applications for 0.5mm Via with 2.69A Capacity
Frequently Asked Questions
Can I use fewer than 1 via(s) for 2.69A?
Reducing the number of vias raises the temperature rise above 10°C for the same current, because the same current flows through less copper. Whether a higher rise is acceptable depends on your board's thermal limit; use the calculator above to see the estimate for other via counts.
Should I use filled or hollow vias for 0.5mm?
For power vias like 0.5mm, hollow vias with multiple parallel vias (as shown here with 1 vias) are typically more cost-effective than filled vias. Filled vias provide better thermal performance but at higher manufacturing cost.
What spacing should I use between 1 parallel vias?
The minimum spacing depends on your fabricator's drill-to-drill, annular-ring and pad-size rules, so check their capability sheet. This calculator does not model current sharing between vias; it assumes the vias are identical and carry equal current.
Related Via Current Calculations
0.5 mm × 1 via compared with other hole sizes
Estimates use 25 µm plating, a 1.6 mm board and 10 °C rise, from the same function as the calculator above.
| Hole | Per via (A) | Vias needed | R per via (mΩ) |
|---|---|---|---|
| 0.2 mm | 1.46 | 2 | 1.59 |
| 0.3 mm | 1.90 | 2 | 1.10 |
| 0.4 mm | 2.31 | 2 | 0.84 |
| 0.5 mm | 2.69 | 1 | 0.68 |
Here 1 parallel via give a combined resistance of 0.68 mΩ and drop 1.8 mV at the estimated limit. The estimate treats the barrel alone: connecting traces and planes usually limit the real path first. Open the full via calculator. To size the connecting trace, open the trace width calculator prefilled with 2.5 A (this via set's estimated limit rounded down, not your design current; assumes 1 oz external).
Complete Your PCB Design
After calculating via current for 0.5mm with 1 via(s), use our other free tools to complete your PCB design. Calculate trace widths for power traces, or analyze impedance for high-speed signals.